We hypothesized that genetic polymorphism in other NER genes, such as XPB (Xeroderma pigmentosum group B), XPC (Xeroderma pigmentosum group C) and XPF (Xeroderma pigmentosum group F), which have not been studied, may be related to an individual’s susceptibility to benzene toxicity. The gene discussed is ERCC3; the disease is xeroderma pigmentosum-Cockayne syndrome complex.